<!DOCTYPE html>
<meta charset="utf-8">
<title>iframe sensor tester</title>
<script src="/generic-sensor/resources/generic-sensor-helpers.js"></script>
<script>
  let mockBackend = null;
  let sensor = null;
  let sensorType = null;

  async function messageHandler(e) {
    if (e.data.command === 'create_sensor') {
      if (!sensor) {
        mockBackend = await initialize_generic_sensor_tests();
        sensor = new self[e.data.type]();
        sensorType = e.data.type;
      }

      return Promise.resolve('success');
    } else if (e.data.command === 'start_sensor') {
      if (!sensor) {
        return Promise.reject('"create_sensor" must be called first');
      }

      return new Promise(resolve => {
        sensor.addEventListener('reading', () => {
          resolve('success');
        }, { once: true });
        sensor.start();
      });
    } else if (e.data.command === 'is_sensor_suspended') {
      if (!mockBackend) {
        return Promise.reject('"create_sensor" must be called first');
      }

      const mockPlatformSensor = await mockBackend.getSensorProvider().getCreatedSensor(sensorType);
      return Promise.resolve(!mockPlatformSensor.isReadingData());
    } else if (e.data.command === 'reset_sensor_backend') {
      if (sensor) {
        sensor.stop();
        await mockBackend.reset();

        sensor = null;
        mockBackend = null;
      }
      return Promise.resolve('success');
    } else {
      return Promise.reject(`unknown command "${e.data.command}"`);
    }
  }

  window.onmessage = async (e) => {
    let reply;
    try {
      reply = await messageHandler(e);
    } catch (error) {
      reply = error;
    }
    e.source.postMessage({ command: e.data.command, result: reply }, '*');
  }
</script>
